#define _CRT_SECURE_NO_WARNINGS  1

class Solution {
public:
    int removeDuplicates(vector<int>& nums)
    {
        if (nums.size() == 1)
            return 1;
        vector<int>::iterator it = nums.begin();
        vector<int>::iterator it1 = it;
        it1++;

        while (it != nums.end())
        {
            while (it1 != nums.end() && *it1 == *it)
                it1++;
            it = nums.erase(++it, it1);
            it1 = it;
            it1++;
        }
        return nums.size();
    }
};